Respuesta :
h=6+b
a=(1/2)bh
a=56
56=(1/2)bh
times 2 both sides
112=bh
h=6+b
a=(1/2)bh
a=56
56=(1/2)bh
times 2 both sides
112=bh
h=6+b
112=b(6+b)
112=b²+6b
minus 112 both sides
0=b²+6b-112
factor
what 2 numbers multily to get -112 and add to get 6
-8 and 14
0=(b-8)(b+14)
set to zero
b-8=0
b=8
b+14=0
b=-14
false, measures can't be negative
base=8
h=6+b
h=6+8
h=14
height=14
base=8
Use the formula for the area of a triangle. The length of the base will be 8 metres.
Given,
The area of triangle is 56 square meter.
Let the length of base be x meter.
So, the height of the triangle will be x+6 meters.
We have to calculate the length of the base.
How to get the area of a triangle?
We know that Area of triangle is,
[tex]A=\dfrac{1}{2} \times Base\times Height[/tex]
[tex]56=\dfrac{1}{2}\times x\times (x+6)[/tex]
[tex]112=x^{2} +6x[/tex]
[tex]x^{2} +6x-112=0\\[/tex]
How to solve a quadratic equation?
On solving the above quadratic equation by middle term split method we get,
[tex]x^{2} +14x-8x-112=0\\[/tex]
[tex]x(x+14)-8(x+14)=0[/tex]
[tex](x+14)(x-8)=0[/tex]
When
[tex]x+14=0\\[/tex]
[tex]x=-14[/tex]
And when
[tex]x-8=0\\[/tex]
[tex]x=8[/tex]
Since side cannot be negative so neglecting the negative value of x, the final value of x will be 8.
Hence the correct option is B. 8 meter.
For more details about triangles, follow the link:
https://brainly.com/question/15442893